Chap 8: Nervous System (Transes) Flashcards
Brain and spinal cord
CNS
All the nervous tissue outside the CNS, including nerves and ganglia.
PNS
also known as
afferent division; conducts action
potentials from sensory receptors to
the CNS
Sensory division
neurons that
transmit action potentials from the
periphery to the CNS
Sensory neurons
also known as
efferent division; PNS conducts
action potentials from the CNS to
effector organs, such as muscles and
glands
Motor division:
neurons that
transmit action potentials from the
CNS toward the periphery
Motor neurons
Transmits
action potentials from the CNS to cardiac
muscle, smooth muscle, and glands
Autonomic nervous system:
transmits action
potentials from the CNS to skeletal muscles
Somatic nervous system
unique
subdivision of the peripheral nervous
system
Enteric nervous system
The two types of cells that make up the
nervous system are
neurons and glial cells
Also known as nerve cells
NEURONS
contains single nucleus;
source of information for gene
expression
Cell Body
receive information from
other neurons or from sensory
receptors and transmit the
information toward the neuron cell
body
Dendrites
formed
when axon remain
unbranched
Collateral axons
area where the
axon leaves the neuron cell
body
Axon hillock
The supportive cells of the CNS and PNS,
meaning these cells do not conduct action
potentials
GLIAL CELLS
closed until
opened by specific signals
Gated channels
cell membrane with
uneven distribution of charge
Polarized
always open; ions
can “leak” across the membrane
down their concentration gradient
Leak channels
opened by neurotransmitters or other
chemicals
Chemically gated channels
opened by
a change in membrane potential
Voltage-gated channels
where action potential starts; triggers nerve impulse
Axon hillock
where neurotransmitters are released
terminal boutons
where saltatory conduction occurs
nodes of ranvier
